Molecular Weight Analysis of Blue Shark (Prionace glauca) Collagen Hydrolysates by GPC-LS. Effect of High Molecular Weight Hydrolysates on Fibroblast Cultures: mRNA Collagen Type I Expression and Synthesis

High molecular weight (Mw) collagen hydrolysates have been demonstrated to produce a higher synthesis of collagen type I mRNA. Mw determination is a key factor maximizing the effect of collagen hydrolysates on collagen type I synthesis by fibroblasts. This work aimed to achieve a high average Mw in Blue Shark Collagen Hydrolysate, studying different hydrolysis parameters by GPC-LS analysis and testing its effect on mRNA Type I collagen expression. Analysis revealed differences in blue shark collagen hydrolysates Mw depending on hydrolysis conditions. Papain leads to obtaining a significantly higher Mw hydrolysate than Alcalase at different times of hydrolysis and at different enzyme/substrate ratios. Besides, the time of the hydrolysis factor is more determinant than the enzyme/substrate ratio factor for obtaining a higher or lower hydrolysate Mw when using Papain as the enzyme. Contrary, Alcalase hydrolysates resulted in similar Mw with no significant differences between different conditions of hydrolysis assayed. Blue shark collagen hydrolysate showing the highest Mw showed neither cytotoxic nor proliferation effect on fibroblast cell culture. Besides, it exhibited an increasing effect on both mRNA expression and pro-collagen I production.

Preparation and Evaluation of the Curative Effect of Blue Shark (Prionace glauca) Skin Collagen Composite Gel in a Rat Oral Ulcers Model

Objective: To evaluate the curative effect of blue shark skin collagen composite gel on oral mucosal ulcer using the rat oral ulcers model stimulated by glacial acetic acid. Methods: Collagen from blue shark skin was isolated and physiochemically characterized by FTIR, SDS-PAGE and scanning electron microscopy (SEM). Seventy standard male rats were divided into seven groups. The surface and the area of the ulcer were observed and calculated daily. After 12 days of administration, rats in the model group and the control group were killed and the ulcer and surrounding tissues were cut to pieces about one mm3 size. The specimens were stained with 10% formalin solution, paraffinembedded sections, HE staining and light microscope were used to observe the histopathological changes in ulcer tissues. Results: The high-dose group had the fastest ulcer healing effects after 12 days of treatment with blue shark skin collagen composite gel. The composite gel was found to significantly accelerate the healing of oral ulcers in a dose-dependent manner. Conclusion: The blue shark skin collagen composite gel in this study may be a good biomedical material candidate for the treatment of oral ulcers in the near future. Potential of other marine fish skin collagen comples on healing oral ulcers should be also considered.

Population parameter, size distribution and sex ratio of the blue shark (Prionace glauca Linnaeus, 1758) caught in the southern of Nusa Tenggara

The blue shark (Prionace glauca Linnaeus, 1758) was a targeted shark caught in the artisanal fisheries in Tanjung Luar, West Nusa Tenggara. This species was caught by drifting longline. The study aims to obtain the parameter population, size distribution and sex ratio of the blue shark from these waters. The research was conducted in Tanjung Luar during 2019-2020, and a total of 1676 blue sharks were caught by drift longline. The data were analyzed by using ELEFAN II. The size blue sharks varied from 73 cm to 397 cm total length (TL), with mean length was 266 cm for males and 72-390 cm with mean length 255,61 cm TL for females. Male was dominated sex ratio. The equation growth for blue shark for male was Lt = 400 (1 – e−0.28 (t-0.2921)) and female was Lt = 390 (1 – e−0.25 (t-0.3307)) . The first captured (Lc ) length for males and females are 267.76 cm and 250.98 cm, respectively. Natural mortality (M) = 0.42/year, the fishing mortality (F ) = 0.50/year. The exploitation rate was > 0.55/year it means that utilization rate of blue sharks in Southern of Nusa Tenggara waters was susceptible to overfishing. This condition needs good management actions for this species.